A flue for recovering waste heat from exhaust gas of coal-fired unit

Abstract

The invention discloses a flue for recovering waste heat from exhaust gas of a coal-fired unit, and relates to the technical field of waste heat recovery. The key points of the technical scheme are: it comprises a flue pipe, and a heat energy recovery device installed in the flue pipe, and also comprises a filter box and a water storage tank installed on the flue pipe, the filter box and the water storage tank are connected by a connecting pipe, and a mounting frame is installed in the flue pipe at a position corresponding to the heat energy recovery device, a sieve plate is slidably connected to the mounting frame, and the mounting frame is connected to a cleaning mechanism through a supporting frame, the cleaning mechanism is used to clean the sieve plate, the cleaning mechanism comprises a motor and a connecting seat installed on the supporting frame, a driving end of the motor is connected to a driving gear, the driving gear is rotatably connected in the connecting seat, and a connecting rod is rotatably installed on the connecting seat, so that the effect is to prevent particulate matter from adhering to the heat energy recovery device and affecting its heat absorption performance, and at the same time, the sieve plate can be cleaned, saving labor.

Description

Technical Field

[0001] The invention relates to the technical field of waste heat recovery, and more specifically, to a flue for recovering waste heat from smoke exhaust of a coal-fired unit. Background Art

[0002] During operation, coal-fired units generate a large amount of energy to generate electricity by burning coal, but they also produce high-temperature flue gas. If these high-temperature flue gases are directly discharged into the atmosphere without any treatment, they will release a large amount of heat into the environment, causing environmental problems such as the heat island effect, the so-called thermal pollution. At the same time, these flue gases also contain rich thermal energy resources, and direct discharge is equivalent to wasting these recoverable thermal energy. In order to improve energy utilization efficiency and reduce environmental pollution, in existing technical solutions, heat energy recovery devices are usually installed in the smoke duct. These recovery devices are well designed and can effectively recover heat energy from high-temperature flue gases, and then convert them into other forms of usable energy, such as preheating boiler feed water or generating steam.

[0003] However, in the actual operation of coal-fired units, we found that the flue gas produced by coal combustion is not pure, but contains many incompletely burned particles, such as coal ash, dust, and other impurities. When these impure flue gases pass through the heat recovery device, the particles and impurities can easily adhere to and accumulate on the surface and internal channels of the heat recovery device due to physical and chemical effects such as condensation and adhesion during the heat exchange process. Since the heat recovery device, especially its heat absorption end, needs to maintain high thermal conductivity to maximize the recovery efficiency of heat energy, the adhesion of particles and impurities will form an insulating layer, which seriously hinders the transfer of heat. This not only reduces the recovery efficiency of the heat recovery device, but may also cause the working condition of the heat recovery device to deteriorate and even cause failures.

[0004] To solve this problem, the current common practice in the industry is to arrange for special personnel to regularly clean the heat recovery device and remove the attached impurities through physical or chemical methods. However, this cleaning process usually requires shutdown, which is not only cumbersome to operate, but also requires a lot of manpower and time resources. In addition, frequent shutdowns for cleaning will interrupt the normal operation of coal-fired units, affecting their overall efficiency and stability, and increasing operation and maintenance costs.

[0005] Therefore, in order to solve the above technical problems, the present invention proposes a flue for recovering waste heat from exhaust gas of a coal-fired unit. Summary of the invention

[0006] In view of the deficiencies in the prior art, the object of the present invention is to provide a flue for recovering waste heat from exhaust gas of a coal-fired unit.

[0007] To achieve the above object, the present invention provides the following technical solution: a flue for recovering waste heat from exhaust gas of a coal-fired unit, comprising a flue pipe, and a heat energy recovery device installed in the flue pipe, and further comprising:

[0008] A filter box and a water storage tank are installed on the flue pipe, and the filter box and the water storage tank are connected through a connecting pipe;

[0009] A mounting frame installed in the flue pipe at a position corresponding to the heat recovery device, a sieve plate being slidably connected to the mounting frame, and a cleaning mechanism being connected to the mounting frame through a supporting frame, the cleaning mechanism being used to clean the sieve plate, the cleaning mechanism comprising a motor and a connecting seat installed on the supporting frame, a driving end of the motor being connected to a driving gear, the driving gear being rotatably connected in the connecting seat, a connecting rod being rotatably installed on the connecting seat, a connecting tooth being installed on the connecting rod being meshed with the driving gear, and a plurality of cleaning brushes being rotatably installed on the connecting rod;

[0010] A transmission tooth rotatably mounted in the connecting rod, the transmission tooth is connected to a plurality of cleaning brushes through a chain, and each of the cleaning brushes is provided with a tooth groove meshing with the chain, and a limit tooth is rotatably mounted on the connecting seat at a position corresponding to the transmission tooth, the limit tooth is meshingly connected with the transmission tooth, and the limit tooth is connected to the driving end of the motor;

[0011] A connecting groove is provided in the flue pipe corresponding to the position of the sieve plate, and the flue pipe is connected to the filter box through the connecting groove. A nozzle is also installed in the flue pipe at the position corresponding to the sieve plate, and the nozzle is connected to the water storage tank through the water inlet pipe. The installation position of the nozzle also corresponds to the position of one of the cleaning brushes. A reset switch for controlling the opening of the nozzle is installed on the nozzle, and a dial block corresponding to the reset switch is installed on the cleaning brush corresponding to the nozzle;

[0012] The nozzle can also spray the cleaning liquid on the sieve plate, and use the cleaning brush to clean the particles attached to the surface of the sieve plate, so that they fall into the filter box to clean the sieve plate. Since the flue gas contains some corrosive substances, such as sulfur dioxide and nitrogen oxides, which are corrosive chemicals, the cleaning liquid in the water tank can be mixed with sodium hydroxide solution, which can react with the sulfur dioxide and nitrogen oxides remaining on the sieve plate to neutralize, reduce the corrosion of the sieve plate, and extend the service life of the sieve plate;

[0013] The limiting teeth drive the cleaning brush to move on the surface of the screen plate through the transmission teeth and can also rotate on its own, thereby enhancing the cleaning effect of the screen plate. Through the set gear ratio of the driving gear and the connecting teeth and the gear ratio of the limiting teeth and the transmission teeth, the connecting rod is driven by the motor to rotate three circles, the shift block touches the reset switch once, and the driving nozzle sprays the cleaning liquid on the surface of the screen plate. Then, the cleaning brush is driven by the connecting rod and the transmission teeth to clean the screen plate, and the particles remaining on the screen plate flow into the filter box with the cleaning liquid. Through the set spraying frequency, it is possible to save cleaning liquid while achieving a scientific cleaning method.

[0014] Furthermore, a slide groove is provided on the surface of the flue pipe at a position corresponding to the mounting frame, and the sieve plate is slidably connected to the mounting frame via the slide groove, so that the sieve plate can be easily disassembled, maintained, and replaced.

[0015] Furthermore, the mounting bracket is installed in the flue pipe at an inclined angle, which can increase the contact area between the screen plate and the flue gas, and at the same time facilitate impurities and liquid on the screen plate to flow into the filter box through the connecting groove.

[0016] Furthermore, a filtering device is installed in the filter box to filter the liquid after cleaning, so that the filtered water flows into the water storage tank, and can be cleaned again, thereby realizing the recycling of water resources.

[0017] Furthermore, the gear ratio of the driving gear and the connecting tooth is different from the gear ratio of the limiting tooth and the transmission tooth. Under the drive of the motor, the connecting rod rotating under the driving gear and the transmission tooth driven by the limiting tooth have different rotation speeds, resulting in a speed differential, so that the connecting rod can drive the cleaning brush to rotate while also enabling the cleaning brush to rotate on its own.

[0018] Furthermore, the gear ratio of the driving gear and the connecting tooth is 3:2, and the gear ratio of the limiting tooth and the transmission tooth is 1:3, so that when the connecting rod rotates 3 circles driven by the motor, the transmission tooth drives the cleaning brush to rotate 1 circle.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. In the present invention, the particulate matter in the flue gas in the flue pipe can be filtered by installing a sieve plate in the flue pipe, the nozzle sprays the cleaning liquid on the sieve plate, and the particulate matter attached to the surface of the sieve plate is cleaned by a cleaning brush to make it fall into the filter box, thereby preventing the particulate matter from attaching to the heat recovery device and affecting its heat absorption performance, and at the same time, the sieve plate can be cleaned, saving labor, thereby solving the problem in the prior art that personnel need to be regularly arranged to clean the heat recovery device, simplifying the cleaning steps, and avoiding affecting the normal operation of the coal-fired unit.

[0021] 2. In the present invention, the motor drives the driving gear and the limiting gear to rotate at the same time. The driving gear drives the cleaning brush to clean the surface of the sieve plate through the connecting rod. The limiting gear drives the cleaning brush to move on the surface of the sieve plate through the transmission gear and can also rotate on its own, thereby enhancing the cleaning effect of the sieve plate. By setting the gear ratio of the driving gear and the connecting gear and the gear ratio of the limiting gear and the transmission gear, the connecting rod is driven by the motor to rotate three circles, the shift block touches the reset switch once, and the driving nozzle sprays the cleaning liquid on the surface of the sieve plate to clean the sieve plate, which can save the spraying of the cleaning liquid. By setting the spraying frequency, the sieve plate can be cleaned more efficiently.

[0022] 3. In the present invention, a motor drives the cleaning brush to rotate on the surface of the screen plate while also allowing it to rotate on its own, thereby enhancing the cleaning effect on the screen plate. There is no need to set up multiple power sources, which reduces procurement costs and increases coordination between equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a schematic diagram of the chute structure in the present invention;

[0026] Figure 3 It is a schematic diagram of the side cross-section structure of the flue pipe in the present invention;

[0027] Figure 4 It is a schematic diagram of the front cross-section structure of the flue pipe in the present invention;

[0028] Figure 5 It is a schematic diagram of the structure of the mounting frame in the present invention;

[0029] Figure 6 It is a schematic diagram of the support frame structure in the present invention;

[0030] Figure 7 It is a schematic diagram of the connecting rod structure in the present invention;

[0031] Figure 8 It is a schematic diagram of the limiting tooth structure in the present invention;

[0032] Fig. 9 It is a schematic diagram of the connecting tooth structure in the present invention;

[0033] Fig.10 It is a schematic diagram of the reset switch structure in the present invention.

[0034] 1. Flue pipe; 2. Water storage tank; 3. Filter box; 31. Filter device; 32. Connecting pipe; 4. Heat recovery device; 5. Mounting frame; 6. Sieve plate; 7. Connecting groove; 9. Nozzle; 91. Water inlet pipe; 10. Cleaning mechanism; 101. Motor; 102. Connecting seat; 103. Connecting rod; 104. Cleaning brush; 105. Driving gear; 106. Connecting teeth; 11. Support frame; 12. Limiting teeth; 121. Chain; 122. Transmission teeth; 13. Shift block; 131. Reset switch; 14. Slide groove. DETAILED DESCRIPTION

[0035] like Figure 1-10 As shown, the present invention provides a flue for recovering waste heat from exhaust gas of a coal-fired unit, comprising a flue pipe 1, and a heat recovery device 4 installed in the flue pipe 1, and further comprising:

[0036] The filter box 3 and the water storage tank 2 are installed on the flue pipe 1, and the filter box 3 and the water storage tank 2 are connected through a connecting pipe 32;

[0037] A mounting frame 5 is installed in the flue pipe 1 at a position corresponding to the heat recovery device 4, a sieve plate 6 is slidably connected to the mounting frame 5, and the mounting frame 5 is connected to a cleaning mechanism 10 through a support frame 11, the cleaning mechanism 10 is used to clean the sieve plate 6, the cleaning mechanism 10 includes a motor 101 and a connecting seat 102 installed on the support frame 11, a driving end of the motor 101 is connected to a driving gear 105, the driving gear 105 is rotatably connected in the connecting seat 102, a connecting rod 103 is rotatably installed on the connecting seat 102, a connecting tooth 106 meshing with the driving gear 105 is installed on the connecting rod 103, and a plurality of cleaning brushes 104 are rotatably installed on the connecting rod 103;

[0038] A transmission tooth 122 is rotatably mounted in the connecting rod 103, and the transmission tooth 122 is connected to a plurality of cleaning brushes 104 through a chain 121, and each cleaning brush 104 is provided with a tooth groove meshing with the chain 121, and a limit tooth 12 is rotatably mounted on the connecting seat 102 at a position corresponding to the transmission tooth 122, and the limit tooth 12 is meshingly connected with the transmission tooth 122, and the limit tooth 12 is connected to the driving end of the motor 101;

[0039] A connecting groove 7 is provided in the flue pipe 1 at a position corresponding to the sieve plate 6, and the flue pipe 1 is connected to the filter box 3 through the connecting groove 7. A nozzle 9 is also installed at a position corresponding to the sieve plate 6 in the flue pipe 1, and the nozzle 9 is connected to the water storage tank 2 through a water inlet pipe 91. The installation position of the nozzle 9 also corresponds to the position of one of the cleaning brushes 104. A reset switch 131 for controlling the opening of the nozzle 9 is installed on the nozzle 9, and a dial block 13 corresponding to the reset switch 131 is installed on the cleaning brush 104 corresponding to the nozzle 9;

[0040] In summary, compared with the case where the heat recovery device 4 is directly installed in the flue pipe 1, Figure 3-4 In the present invention, a sieve plate 6 is installed in front of the heat recovery device 4 in the flue pipe 1. The sieve plate 6 can filter the particulate matter in the flue gas in the flue pipe 1 to prevent the particulate matter from being adsorbed on the surface of the heat recovery device 4 and affecting the heat recovery of the heat recovery device 4.

[0041] See also Figure 4-5 The nozzle 9 can also spray the cleaning liquid on the sieve plate 6, and clean the particles attached to the surface of the sieve plate 6 through the cleaning brush 104, so that the particles fall into the filter box 3 to clean the sieve plate 6. Since the flue gas contains some corrosive substances, such as sulfur dioxide and nitrogen oxides, which can corrode the sieve plate 6, the cleaning liquid in the water tank 2 can be mixed with sodium hydroxide solution, which can react with the sulfur dioxide and nitrogen oxides remaining on the sieve plate 6 to neutralize, reduce the corrosion of the sieve plate 6, and extend the service life of the sieve plate 6;

[0042] See also Figure 5-7 When cleaning the sieve plate 6, the motor 101 drives the driving gear 105 and the limiting tooth 12 to rotate at the same time, and the driving gear 105 drives the cleaning brush 104 to rotate on the surface of the sieve plate 6 through the connecting rod 103 to clean the sieve plate 6;

[0043] The gear ratio of the driving gear 105 and the connecting teeth 106 is different from the gear ratio of the limiting teeth 12 and the transmission teeth 122. When driven by the motor 101, the connecting rod 103 driven by the driving gear 105 and the transmission teeth 122 driven by the limiting teeth 12 have different rotation speeds, and there is a speed difference, so that the connecting rod 103 drives the cleaning brush 104 to rotate and the cleaning brush 104 can also rotate on its own.

[0044] Specifically, the gear ratio of the driving gear 105 and the connecting gear 106 is 3:2, and the gear ratio of the limiting gear 12 and the transmission gear 122 is 1:3, so that when the connecting rod 103 rotates 3 times under the drive of the motor 101, the transmission gear 122 drives the cleaning brush 104 to rotate 1 time;

[0045] See also Figure 7-10, the limiting tooth 12 drives the cleaning brush 104 to move on the surface of the sieve plate 6 through the transmission tooth 122, and can also rotate on its own, thereby enhancing the cleaning effect of the sieve plate 6, and through the set gear ratio of the driving gear 105 and the connecting tooth 106 and the gear ratio of the limiting tooth 12 and the transmission tooth 122, the connecting rod 103 is driven by the motor 101 to rotate three circles, the shift block 13 contacts the reset switch 131 once, and the driving nozzle 9 is driven to spray the cleaning liquid on the surface of the sieve plate 6, and then the cleaning brush 104 is driven by the connecting rod 103 and the transmission tooth 122 to clean the sieve plate 6, and the particles remaining on the sieve plate 6 flow into the filter box 3 along with the cleaning liquid, and through the set spraying frequency, it is possible to save the cleaning liquid while achieving a scientific cleaning method;

[0046] It is worth noting that a slide groove 14 is provided on the surface of the flue pipe 1 at a position corresponding to the mounting frame 5, and the sieve plate 6 is slidably connected to the mounting frame 5 through the slide groove 14, so that the sieve plate 6 is easily disassembled, maintained and replaced;

[0047] It should be noted that the mounting frame 5 is installed in the flue pipe 1 at an inclined angle, which can increase the contact area between the sieve plate 6 and the flue gas, and facilitate the impurities and liquid on the sieve plate 6 to flow into the filter box 3 through the connecting groove 7;

[0048] Among them, a filtering device 31 is installed in the filter box 3 to filter the liquid after cleaning, so that the filtered water flows into the water storage tank 2, and can be cleaned again to achieve the recycling of water resources.

[0049] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in the industry can smoothly implement the present invention as shown in the drawings and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A flue for recovering waste heat from exhaust gas of a coal-fired unit, comprising a flue pipe (1) and a heat recovery device (4) installed in the flue pipe (1), characterized in that: Also includes: A filter box (3) and a water storage tank (2) installed on the flue pipe (1), wherein the filter box (3) and the water storage tank (2) are connected via a connecting pipe (32); A mounting frame (5) is installed in a flue pipe (1) at a position corresponding to a heat recovery device (4), a sieve plate (6) being slidably connected to the mounting frame (5), and the mounting frame (5) is connected to a cleaning mechanism (10) via a support frame (11), the cleaning mechanism (10) being used to clean the sieve plate (6), the cleaning mechanism (10) comprising a motor (101) and a connecting seat (102) installed on the support frame (11), a driving end of the motor (101) being connected to a driving gear (105), the driving gear (105) being rotatably connected in the connecting seat (102), a connecting rod (103) being rotatably installed on the connecting seat (102), a connecting tooth (106) being installed on the connecting rod (103) and meshingly connected to the driving gear (105), and a plurality of cleaning brushes (104) being rotatably installed on the connecting rod (103); A transmission tooth (122) is rotatably mounted in the connecting rod (103), the transmission tooth (122) being connected to a plurality of cleaning brushes (104) via a chain (121), and each of the cleaning brushes (104) is provided with a tooth groove meshingly connected to the chain (121), and a limit tooth (12) is rotatably mounted on the connecting seat (102) at a position corresponding to the transmission tooth (122), the limit tooth (12) being meshingly connected to the transmission tooth (122), and the limit tooth (12) is connected to the driving end of the motor (101); A connecting groove (7) is provided in the flue pipe (1) at a position corresponding to the sieve plate (6), and the flue pipe (1) is connected to the filter box (3) through the connecting groove (7). A nozzle (9) is also installed at a position corresponding to the sieve plate (6) in the flue pipe (1), and the nozzle (9) is connected to the water storage tank (2) through a water inlet pipe (91). The installation position of the nozzle (9) also corresponds to the position of one of the cleaning brushes (104). A reset switch (131) for controlling the opening of the nozzle (9) is installed on the nozzle (9), and a shift block (13) corresponding to the reset switch (131) is installed on the cleaning brush (104) corresponding to the nozzle (9).

2. A flue for recovering waste heat from exhaust gas of a coal-fired unit according to claim 1, characterized in that: A slide groove (14) is provided on the surface of the flue pipe (1) at a position corresponding to the mounting frame (5), and the sieve plate (6) is slidably connected to the mounting frame (5) via the slide groove (14).

3. A flue for recovering waste heat from exhaust gas of a coal-fired unit according to claim 2, characterized in that: The mounting frame (5) is installed in the flue pipe (1) at an inclined angle.

4. A flue for recovering waste heat from exhaust gas of a coal-fired unit according to claim 3, characterized in that: A filtering device (31) is installed in the filtering box (3).

5. A flue for recovering waste heat from exhaust gas of a coal-fired unit according to claim 4, characterized in that: The gear ratio between the driving gear (105) and the connecting gear (106) is different from the gear ratio between the limiting gear (12) and the transmission gear (122).

6. A flue for recovering waste heat from exhaust gas of a coal-fired unit according to claim 5, characterized in that: The gear ratio between the driving gear (105) and the connecting gear (106) is 3:2, and the gear ratio between the limiting gear (12) and the transmission gear (122) is 1:3.

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